Rodrigues M C, Rezende W M, Silva M E J, Faria S V, Zuffo L T, Galvão J C C, DeLima R O
Departamento de Fitotecnia, Universidade Federal de Viçosa, Viçosa, MG, Brasil.
Departamento de Fitotecnia, Universidade Federal de Viçosa, Viçosa, MG, Brasil
Genet Mol Res. 2017 Sep 21;16(3):gmr-16-03-gmr.16039757. doi: 10.4238/gmr16039757.
Improvement in nitrogen-use efficiency (NUE) on maize is among the best strategies to mitigate the problems of poor soil fertility in tropical conditions. The objectives of this study were: i) to quantify the genetic variability for NUE-components and agronomic traits in a set of tropical maize inbred lines; ii) to study the genetic divergence among tropical maize inbred lines under contrasting nitrogen (N) levels; iii) to identify the secondary traits associated with NUE in tropical maize inbred lines; and iv) to identify maize inbred lines efficient in NUE and its components. Sixty-four tropical maize inbred lines were evaluated in the field under low- and high-N conditions for NUE-components and agronomic traits. Genetic variability for NUE-components and agronomic traits was found; lines in eight different groups for each N condition were allocated, and N-efficient inbred lines were identified in different groups. Furthermore, we suggest flowering time traits and kernel number as great secondary traits for selecting tropical maize inbred lines for NUE under both N conditions, and chlorophyll content for selecting for NUE under N stress.
提高玉米的氮素利用效率（NUE）是缓解热带条件下土壤肥力低下问题的最佳策略之一。本研究的目的是：i）量化一组热带玉米自交系中NUE组分和农艺性状的遗传变异；ii）研究不同氮（N）水平下热带玉米自交系之间的遗传差异；iii）鉴定热带玉米自交系中与NUE相关的次要性状；iv）鉴定NUE及其组分高效的玉米自交系。在田间低氮和高氮条件下对64个热带玉米自交系的NUE组分和农艺性状进行了评价。发现了NUE组分和农艺性状的遗传变异；针对每种氮条件，将自交系分配到八个不同的组中，并在不同组中鉴定出氮高效自交系。此外，我们建议，在两种氮条件下，开花时间性状和籽粒数是选择热带玉米自交系NUE的重要次要性状，而叶绿素含量是在氮胁迫下选择NUE的次要性状。
